That is the question posed by one John Bambenek, who filed a complaint with the FEC asking them to regulate the Daily Kos as a political committee. I cannot answer it better than Jim Robinson, the founder of Free Republic, did in the Free Republic thread on it:
Not only no, but hell no! The first amendment protects our God-given unalienable rights to free speech, free press, freedom to dissent and freedom of association. All of the campaign laws enacted by congress in violation of the first amendment should be repealed as unconstitutional and the FEC disbanded.